Apparatus for fixing cervical spine

ABSTRACT

Disclosed herein is an apparatus for fixing a cervical spine. The apparatus for fixing a cervical spine includes a plate in which a plurality of screw insertion holes is formed, bone screws inserted into the screw insertion holes and screwed onto a bone fragment through rotation, and a locking part rotatably coupled to the plate to open or close a top of the screw insertion hole. A stepped part of a specific depth is formed on top of the plate. The stepped part includes a rotation area in which the locking part is capable of rotating. A locking part insertion hole is formed in the rotation area so that the locking part is inserted into locking part insertion hole.

FIELD OF THE INVENTION

The present invention relates to an apparatus for fixing a cervicalspine, which is used when an operation for fixing the front of acervical spine is performed in orthopedics or neurosurgery and, moreparticularly, to an apparatus for fixing a cervical spine, which caneasily fix a bone screw inserted into the screw insertion hole of aplate using a rotatable locking part.

BACKGROUND OF THE INVENTION

In general, in orthopedics or neurosurgery, when a cervical spineintervertebral disc disease, a cervical spine disk, cervicospinalmyelosis or a cervical spine fracture is treated, cervical spines mustbe fixed to not move. To this end, an apparatus for fixing a cervicalspine, including a plate of a sheet form and a screw for fixing theplate to a cervical spine, is used.

A surgical procedure using the apparatus for fixing a cervical spine isperformed in such a way as to cut a lesion from the neck portion of apatient, expose a cervical spine, to perform a surgical procedurematter, such as a cage for the cervical spine, on the cervicalspondylosis lesion, to locate the plate at the top and bottom of thelesion, and then to fix a corresponding plate by a screw.

Accordingly, the surgical procedure matter, such as the cage that hasoperated on the cervical spine, is fixed by fixation power of the screwand bearing power of the plate of the apparatus for fixing a cervicalspine.

However, a phenomenon in which the screw becomes loose from the plate ofthe apparatus for fixing a cervical spine due to the activities of apatient after a surgical procedure and then retreats from the plate maybe generated. From among conventional technologies for preventing such aphenomenon, Korean Patent No. 10-0552117 (CERVICAL SPINE FIXATOR ANDDRIVER) and U.S. Patent Application Publication No. US 2016-0095637(LOCKING MECHANISM FOR A CERVICAL FIXATION PLATE) have been known.

The contents of the prior arts are described below. In Korean Patent No.10-0552117, the deviation of a screw is prevented by inserting the screwinto an open part formed in a plate and seating a fixing member in areset part. In U.S. Patent Application Publication No. US 2016-0095637,the deviation of a bone screw is prevented by inserting the bone screwinto a bone screw opening formed in a plate body and coupling a lockingelement to a rocking post.

However, Korean Patent No. 10-0552117 has a problem in that it isinconvenient to perform rivet coupling on the plate in order to seat thefixing member. U.S. Patent Application Publication No. US 2016-0095637has problems in that the locking element protruded outside the platebody may be caught in another thing and damaged due to a movement of apatient and the rocking post must be separated processed in the platebody.

PRIOR ART DOCUMENT Patent Document

(Patent Document 1) Korean Patent No. 10-0552117

(Patent Document 2) U.S. Patent Application Publication No. US2016-0095637

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made keeping in mind theabove problems occurring in the prior art, and an object of the presentinvention is to provide an apparatus for fixing a cervical spine, whichcan prevent a locking part from deviating from a plate or from beingcaught and damaged despite the activities of a patient because thelocking part for preventing the drawing of a bone screw is seated in astepped part and allows an operator to simply prevent the drawing of thebone screw by rotating the locking part.

An embodiment of the present invention provides an apparatus for fixinga cervical spine, including a plate in which a plurality of screwinsertion holes is formed, bone screws inserted into the screw insertionholes and screwed onto a bone fragment through rotation, and a lockingpart rotatably coupled to the plate to open or close a top of the screwinsertion hole. A stepped part of a specific depth is formed on top ofthe plate. The stepped part includes a rotation area in which thelocking part is capable of rotating. A locking part insertion hole isformed in the rotation area so that the locking part is inserted intolocking part insertion hole.

The locking part includes a vertical part inserted into the locking partinsertion hole, a horizontal part integrally coupled to the verticalpart and coming into surface contact with the rotation area, and aplurality of fixing wings formed in the horizontal part andsimultaneously opening or shutting the tops of two screw insertion holesadjacent to the rotation area.

An angle between the plurality of fixing wings is 120°.

A central area to guide the rotation of the locking part is providedbetween a plurality of the rotation areas provided in the stepped part,the fixing wing located in the rotation area shuts the top of the screwinsertion hole, and the fixing wing located in the central area opensthe top of the screw insertion hole.

A molding head part is formed at one end of the vertical part in orderto prevent the locking part from being drawn after the locking part isinserted into the locking part insertion hole.

A rotation hole is formed in the horizontal part so that the rotationhole is coupled to a rotation tool and rotates the locking part.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view of an apparatus for fixing acervical spine according to an embodiment of the present invention.

FIG. 2 is a rear view of the apparatus for fixing a cervical spineaccording to an embodiment of the present invention.

FIG. 3 is a plan view showing the state in which the fixing wing of theapparatus for fixing a cervical spine is located in a central areaaccording to an embodiment of the present invention.

FIG. 4 is a plan view showing the state in which the fixing wing shownin FIG. 3 has rotated 90°.

FIG. 5 is a plan view showing the state in which the fixing wing shownin FIG. 3 is located in a rotation area.

<Description of reference numerals> 1: apparatus for fixing a cervicalspine 10: plate 12a, 12b, 12c: screw insertion hole 14a, 14b, 14c:locking part insertion hole 16: first stepped part 17: second steppedpart 18: vision hole 19: vision hole 20: bone screw 22: head part 24:shaft 26: clamping device hole 30: locking part 32: vertical part 33:molding head part 34: horizontal part 35a, 35b: fixing wing 36: rotationhole

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of an apparatus for fixing a cervical spine according tothe present invention described in detail with reference to theaccompanying drawings. Terms or words used herein should not beconstrued as having common or dictionary meanings, but should beconstrued as having meanings and concepts that comply with thetechnological spirit of the present invention on the basis of theprinciple that the inventor may appropriately define the concepts of theterms in order to best describe his or her invention.

Referring to FIG. 1, the apparatus 1 for fixing a cervical spineaccording to an embodiment of the present invention can easily fix abone screw 20 inserted into a plate 10 at a desired angle, and includesthe plate 10, the bone screw 20 and a locking part 30.

The plate 10 is fixing means used to fix a bone fragment generated inthe body of a person or an animal and has an approximately rectangularparallelepiped panel shape. The plate is outward protruded along thecurved surface of a portion to which the bone screw 20 is coupled. Theshape of the plate 10 may be changed depending on the shape of a bonefragment.

The plate 10 may be made of a rigid metal material, such as titanium, ora polymer material, such as polyether ether ketone, but the shape andmaterial of the plate 10 are not limited to the aforementioned shape andmaterials. A rigid material for fixing a bone fragment which does not anadverse reaction when it is inserted into the human body may be used.The plate 10 includes screw insertion holes 12 a, 12 b and 12 c andstepped parts 16 and 17.

The bone screws 20 to be described later are inserted into the screwinsertion holes 12 a, 12 b and 12 c. An insertion path that penetratesfrom the top of the plate 10 to the bottom is formed. The screwinsertion holes 12 a, 12 b and 12 c are formed to be symmetrical to anaxis in the length direction of the plate 10. Three pairs of the screwinsertion holes 12 a, 12 b and 12 c have been shown in FIG. 1, but thescrew insertion holes 12 a, 12 b and 12 c that are more than three pairsor less than three pairs may be configured in the plate 10.

Central axes formed in the screw insertion holes 12 a, 12 b and 12 c maybe perpendicular to the top and bottom of the plate 10, but may beconfigured at a specific angle. For example, as shown in FIG. 1, thecentral axes of a pair of the screw insertion holes 12 a that belong tothe three pairs of screw insertion holes 12 a, 12 b and 12 c and thatare located on the upper side may be configured to become close eachother. The central axes of a pair of the screw insertion holes 12 b thatbelong to the three pairs of screw insertion holes 12 a, 12 b and 12 cand that are located in the middle may be configured in the directionperpendicular to the top and bottom of the plate 10. The central axes ofa pair of the screw insertion holes 12 c that belong to the three pairsof screw insertion holes 12 a, 12 b and 12 c and that are located on thelower side may be configured to become distant from each other. Theangles of the central axes are formed by processing the screw insertionholes 12 a, 12 b and 12 c in the direction of the central axis dependingon the shape of a bone fragment to be fixed.

The inner surface of the screw insertion hole 12 a, 12 b, 12 c may beformed to have a tapered surface or may be formed as a counter boreposition having a latching jaw through the upper hole and the lower holeso that after the bone screw 20 is inserted into a cervical spine, theplate 10 is not drawn to a direction opposite the direction in which thebone screw 20 is inserted. In an embodiment of the present invention,the inner surface of the screw insertion hole 12 a, 12 b, 12 c has beenillustrated as having a tapered surface.

The stepped parts 16 are 17 are areas in which steps have been formedfrom the top of the plate 10 to the bottom thereof in order to seat thelocking parts 30. The stepped part may include a rotation area and acentral area. Referring to FIG. 1, the stepped parts 16 and 17 include afirst stepped part 16 and a second stepped part 17. The first steppedpart 16 includes a pair of rotation areas symmetrical to each other onthe basis of the central area. The second stepped part 17 includes acentral area and a rotation area.

The rotation area is provided between the pairs of screw insertion holes12 a, 12 b and 12 c and has a rotation path having specific curvature sothat the locking part 30 can rotate. Locking part insertion holes 14 a,14 b and 14 c that penetrate from the top of the plate 10 to the bottomthereof are configured in the rotation areas. Accordingly, the depth ofthe screw insertion holes 12 a, 12 b and 12 c and the depth of thelocking part insertion holes 14 a, 14 b and 14 c have a differencecorresponding to the step.

The central area is connected to the rotation area and provided betweena pair of the screw insertion holes 12 a and 12 b and between a pair ofthe screw insertion holes 12 b and 12 c. The central areas are spacedapart from each other in the length direction of the plate 10 so that itdoes not hinder rotation between a plurality of the locking parts 30located in the rotation areas. Vision holes 18 and 19 formed to have aform that penetrates the plate 10 and to allow the procedure state ofthe apparatus 1 for fixing a cervical spine to be easily checked areconfigured in the central area.

Referring to FIG. 1, the stepped parts 16 and 17 include the firststepped part 16 and the second stepped part 17. The first stepped part16 has a pair of rotation areas symmetrical to each other on the basisof the central area. The second stepped part 17 has the central area andthe rotation area. However, if four pairs of the screw insertion holesare configured as described above, the second stepped part 17 may have acentral area and a rotation area, such as those of the first steppedpart 16.

The bone screw 20 may include a head part 22 and a shaft 24 in order tobe inserted into the screw insertion hole 12 a, 12 b, 12 c of the plate10.

A clamping device hole 26 into which a clamping device (not shown) isinserted may be formed at the top of the head part 22 so that the bonescrew 20 is coupled to a cervical spine (not shown). In FIG. 1, theclamping device hole 26 has been formed to have a star shape, but mayhave a different shape for coupling the clamping device hole 26 and theclamping device (not shown).

The outer surface of the head part 22 may have a tapered surface in sucha way as to correspond to the inner surface of the screw insertion hole12 a, 12 b, 12 c. That is, the inner surface of the screw insertion hole12 a, 12 b, 12 c and the outer surface of the bone screw 20 can becompressed and brought in contact with each other with inclination dueto the shape of the inner surface of the head part 22. Accordingly,after the bone screw 20 is inserted into the cervical spine, the drawingof the plate 10 is prevented.

The shaft 24 has one end integrally coupled to the head part 22 andinclined toward the other end to have a screw form. A screw threadformed in one direction to be easily coupled to the cervical spine isconfigured in the outer surface of the shaft 24.

As described above, the axis in which the screw insertion hole 12 a, 12b, 12 c is inserted can be processed to be inclined at a specific angle.Accordingly, the bone screw 20 inserted into the inclined screwinsertion hole 12 a, 12 b, 12 c moves with inclination in the directionof the central axis of the screw insertion hole 12 a, 12 b, 12 c andscrew-coupled to the cervical spine. Accordingly, a task for fixing bonefragments of various forms can be performed depending on the angle ofthe central axis of the screw insertion hole 12 a, 12 b, 12 c.

The diameter of the top of the bone screw 20 may be smaller than that ofthe top of the screw insertion hole 12 a, 12 b, 12 c. Accordingly, thebone screw 20 is inserted into the screw insertion hole 12 a, 12 b, 12c, moved and stopped at a portion where the diameter of the top of thebone screw 20 is the same as the diameter of the top of the bone screw20 in the inner surface of the screw insertion hole 12 a, 12 b, 12 c.Accordingly, the top of the bone screw 20 is not protruded outside thetop of the screw insertion hole 12 a, 12 b, 12 c.

The locking part 30 is inserted into the plate 10 and is for fixing thebone screw 20 in order to prevent the drawing of the bone screw 20depending on a rotation angle. The locking part includes a vertical part32 and a horizontal part 34.

Referring to FIGS. 1 and 2, the vertical part 32 has a cylindricalhollow shape so that it is inserted into the locking part insertion hole14 a, 14 b, 14 c provided in the plate 10 and rotated therein. In thestate in which the locking part 30 has been inserted into the lockingpart insertion hole 14 a, 14 b, 14 c, one end of the vertical part 32 iscoupled to the horizontal part 34 and integrated therewith, therebypreventing drawing in the downward direction of the locking part 30.Furthermore, the other end of the vertical part 32 forms a molding headpart 33 a to prevent drawing in the upward direction of the locking part30.

A rotation hole 36 is provided in the horizontal part 34 to communicatewith the hollow of the vertical part 32. When a driver (not shown) isinserted into the rotation hole 36 and rotated, the integrally formedvertical part 32 and horizontal part 34 can rotate in the rotation areaof the stepped part 16, 17 on the basis of the central axis of therotation hole 36. In the state in which the horizontal part 34 has beeninserted into the locking part insertion hole 14 a, 14 b, 14 c, the topof the horizontal part 34 is almost identical with the top of the plate10 due to the depth of the depth of the rotation area. Accordingly, aphenomenon in which the locking part 30 is caught in the outside due toa movement of a patient can be prevented.

Fixing wings 35 a and 35 b are provided on both sides of the horizontalpart 34 so that the top of the screw insertion hole 12 a, 12 b, 12 c isclosed and rotation in the rotation area of the stepped part 16, 17 isfacilitated depending on a rotation angle. FIG. 1 shows the two fixingwings 35 a and 35 b having an angle of 120° between extension lines thatconnect the central axis of the rotation hole 36 and the fixing wings 35a and 35 b (hereinafter referred to as a “wing angle”). However, thewing angle may be set so that an angle between extension lines thatconnects the central axes of the screw insertion holes 12 a, 12 b and 12c adjacent to the locking part insertion holes 14 a, 14 b and 14 c inthe central axes of the locking part insertion holes 14 a, 14 b and 14 c(hereinafter referred to as a “closed angle”). For example, if theclosed angle is 180°, the wing angle may be set to 180°. Furthermore,the number of fixing wings 35 a and 35 b is not limited to 2 and may betwo or more if the top of the screw insertion hole 12 a, 12 b, 12 c canbe closed by the locking part 30. The size and shape of the fixing wings35 a and 35 b may be configured in various manners.

The operation of the locking part 30 is described in detail withreference to FIGS. 3 to 5.

Referring to FIG. 3, the bone screws 20 have been inserted into thescrew insertion holes 12 a, 12 b and 12 c of the plate 10, and thelocking parts 30 have been inserted into the locking part insertionholes 14 a, 14 b and 14 c. The fixing wings 35 a and 35 b of the lockingpart 30 inserted into the locking part insertion hole 14 a over thefirst stepped part 16 and the fixing wings 35 a and 35 b of the lockingpart 30 inserted into the locking part insertion hole 14 b under thefirst stepped part 16 face each other on the basis of the central areaof the first stepped part 16. The fixing wings 35 a and 35 b of thelocking part 30 inserted into the locking part insertion hole 14 c ofthe second stepped part 17 are set toward the central area of the secondstepped part 17. If such setting is performed, the fixing wings 35 a and35 b open the tops of the screw insertion holes 12 a, 12 b and 12 c.Accordingly, when the fixing wings 35 a and 35 b face toward the centralarea of the stepped part 30, the fixing wings 35 a and 35 b do not fixthe bone screw 20 inserted into the screw insertion hole 12 a, 12 b, 12c.

FIG. 4 shows the state in which the fixing wings 35 a and 35 b shown inFIG. 3 has rotated 90° on the basis of the central axis of the rotationhole 36. In this state, the fixing wings 35 a and 35 b do not close thetop of the screw insertion hole 12 a, 12 b, 12 c.

FIG. 5 shows the state in which the fixing wings 35 a and 35 b shown inFIG. 4 have further rotated 90° on the basis of the central axis of therotation hole 36. In this state, the wing angle of the fixing wings 35 aand 35 b becomes the same as the closed angle and the wing angle shutsthe top of the screw insertion hole 12 a, 12 b, 12 c, thereby preventingthe drawing of the bone screw 20 inserted into the screw insertion hole12 a, 12 b, 12 c. Through such a process, the drawing of the bone screw20 inserted into the plate 10 can be easily prevented by only therotation of the locking part 30.

A procedure method using the apparatus 1 for fixing a cervical spineaccording to an embodiment of the present invention is described below.

First, an operator performs an operation of a surgical procedure matter,such as a cage, on the lesion of a patient who has suffered a cervicalspine fracture. The operator covers the lesion with the plate 10 whilechecking an accurate location of the lesion through the vision holes 18and 19.

When the plate 10 comes into contact with the accurate location of thelesion, the operator rotates the locking part 30 formed in the plate 10in the state in which it has opened the top of the screw insertion hole12 a, 12 b, 12 c and inserts the bone screw 20 into the screw insertionhole 12 a, 12 b, 12 c.

Thereafter, the operator couples a clamping device (not shown) to theclamping device hole 26 of the inserted bone screw 20 and performs screwcoupling to a fractured cervical spine by rotating the bone screw 20 inone direction.

When all the bone screws 20 are screwed through the screw insertionholes 12 a, 12 b and 12 c formed in the plate 10, the operator inserts arotation tool, such as a driver (not shown), into the rotation hole 36formed in the locking part 30 and rotates the rotation tool. When thelocking parts 30 close all of the tops of the screw insertion holes 12a, 12 b and 12 c, the operator stops the rotation.

In accordance with an embodiment of the present invention, the drawingof the bone screw can be prevented by shutting the top of the platethrough a simple rotation manipulation of the locking part.

Furthermore, in accordance with an embodiment of the present invention,a phenomenon in which the locking part is caught due to the activitiesof a patient can be prevented because the locking part is seated in thestepped part formed in the plate.

Although the present invention has been described in connection with thelimited embodiments and drawings, the present invention is not limitedto them. A person having ordinary skill in the art to which the presentinvention pertains may change or modify the present invention in variousways within the technological spirit of the present invention and theequivalent range of the claims to be described below.

We claim:
 1. An apparatus for fixing a cervical spine, comprising: aplate in which a plurality of screw insertion holes is formed; bonescrews inserted into the screw insertion holes and configured to bescrewed onto a bone fragment through rotation; and a locking partrotatably coupled to the plate to open or close a top of a screwinsertion hole, wherein a stepped part of a specific depth is formed ontop of the plate, the stepped part comprises a rotation area in whichthe locking part is capable of rotating, a central area to guide therotation of the locking part is provided between a plurality of therotation areas provided in the stepped part, a locking part insertionhole is formed in the rotation area so that the locking part is insertedinto the locking part insertion hole, and a vision hole that penetratesthe plate is formed in the central area so as to check a procedurestate, wherein the locking part includes a plurality of fixing wingsprotruded from the locking part and disposed in a non-radial type withrespect to a center of the locking part, and wherein a fixing wing isoverlapped with the bone screw by rotation to fix the bone screw, thelocking part is provided so as not to overlap with the vision hole. 2.The apparatus of claim 1, wherein the locking part comprises: a verticalpart inserted into the locking part insertion hole; a horizontal partintegrally coupled to the vertical part and coming into surface contactwith the rotation area; and the plurality of fixing wings formed in thehorizontal part and simultaneously opening or shutting tops of two screwinsertion holes adjacent to the rotation area.
 3. The apparatus of claim2, wherein an angle between the plurality of fixing wings is 120°. 4.The apparatus of claim 2, wherein: a fixing wing located in the rotationarea shuts the top of the screw insertion hole, and a fixing winglocated in the central area opens the top of the screw insertion hole.5. The apparatus of claim 2, wherein a molding head part is formed atone end of the vertical part in order to prevent the locking part frombeing drawn after the locking part is inserted into the locking partinsertion hole.
 6. The apparatus of claim 2, wherein a rotation hole isformed in the horizontal part so that the rotation hole is coupled to arotation tool and rotates the locking part.